The use of adjunct processors in conjunction with telecommunications switching systems is well-known in the art. The adjunct processors are used to supplement the capabilities of the switching systems, such as to provide features and services that the switching systems are either incapable or ill-capable of providing. An illustrative example of a commonly-used type of adjunct processor is voice-mail systems.
In order to perform their functions, adjunct processors often have need of information that is contained in the database of the corresponding switching system. In the case of voice-mail systems, this information is the directory information which defines the correspondence between subscribers' names and extension numbers.
Numerous arrangements exist for providing the adjunct processor with this information. Many of today's switches come equipped with a control communications link to which the adjunct processor can attach and over which it can interrogate the database of the switching system. However, most manufacturers of switching systems use proprietary communications protocols on the control communications links, making it difficult, if not impossible, to use any other manufacturers' adjunct processors with their switching systems.
To avoid this difficulty, the adjunct processor may be equipped with its own, independent, database which the owner of the adjunct populates with a copy of the contents of the switching system's database prior to using the adjunct processor. This requires the system owner to administer and maintain two databases--a complex and a time-consuming task. It is also prone to error unless the owner rigorously ensures that all updates to the contents of one database are also timely and identically made to the other database.
To avoid this difficulty, some adjunct processors dispense with accessing switching system database information at their initiative, and instead rely upon the switching system to supply them with the requisite information when it is needed. For example, some switching systems send either the directory name or the directory number of the calling and called parties as display information to whatever terminal they are connecting the call to, and many voice-mail systems rely on this display information to convey to them the requisite directory information at the time that it is needed, i.e., at the beginning of each call. However, in order for the display information to convey the full directory information which the voice-mail system needs, i.e., both the names and the corresponding directory numbers, the contents of the switching system's database must be modified and re-administered so as to include the extension numbers in the name fields of the database records. Such re-administration of the switching system database is complex, costly, cumbersome, and error prone, and hence it is not favored by system owners.
To avoid the re-administration problem, one known messaging system places calls sequentially to every extension number of the switching system at some time of day when this is least likely to interfere with normal operation, e.g., between 2 and 3 o'clock in the morning. In response to every call, the messaging system receives the called party's name as display information from the switching system, and it stores the name and corresponding extension in its own database for future use. However, this is a time-consuming process which seriously interferes with normal operation of systems that are used on an around-the-clock basis. Furthermore, this system is error-prone in that is relies on the messaging system having been previously provided with, and being continually updated with, the complete and correct set of switching system extension numbers, by the system administrator.
Consequently, what the art requires is a simple and accurate way for adjunct processors to obtain up-to-date database information that mirrors switching system database information.